Brett.............as with many things 'each to their own'. My car is now fitted with the Motorsport X, OEM GT resonators and 928 Specialists RMB and its much louder than its ever been but i like it. The car revs very freely when compared to before and has been described by friends and family as a Superbike on 'full song' and a Ferrari. I live in a very rural setting so I can probably get away with the 'loudness'; your local law folks may think differently.

As much as I truly love the car and its sound.............it will never ever be a F1 car..............thats a sound that sends shivers...........pure xtascy.

 

Sounds like a fuel pressure bleed down to me, injectors ect...
Could be as simple as a partially clogged filter, too.
Do the cheap stuff first!

 

I'm bumping this because of an idea I just got. Is it possible to relocate the ISV to perhaps to the left of the throttle cable assembly? It connects to that same hose? I can simply run some vacuum lines further down, and fabricate some sort of mounting bracket for it. Oh, and if the harness cannot reach out that far, I can extend it with additonal splicing and proper connections for the best conduction.

 

Why would you want to?

 

cuz under an intake manifold makes no sense to me but to hide it from poking eyes At least I can get to it later.

 

Oh BTW, if this changes any thoughts...I have done a fuel pump check valve and filter already on this car. Spark plugs can't have more than 2,000 miles on them also.

Car still feels like it has plenty of power on wide open throttle. However, it feels twitchy at a stop because of the fluctuating idle, like it wants to dart forward.

 

Andy-

Why not see if you can swap your MAF with someone else to verify if it's bad or not. Takes 15min, tops! The darting forward sensation is probably because the surging idle is bumping up against the stall speed of the torque converter. Solve the idle and that will go away. Cheers!

 

I'm picking up an MAF today that a buddy of mine is letting me borrow for testing from his shop. It's actually a brand new unit! He said that he really wants to get rid of it. Regardless if mine is dead or not, he'll cut me a steal of a deal for it too

 

I gave this some thought. If the MAF swap doesn't cure the problem, what should I look at next to troubleshoot?

 

UPDATE: Car's fixed! Turns out it was a big Jack in the Box wrapper stuck in the air box.

 

Good to hear and perhaps a lessoned learned in 101 mechanics..............check the fundamentals first; good compression, ingnition at the correct time and the correct air/fuel mixture.

Hopefully you didn't buy the MAF, Temp II sensor and the ISV.

 

UPDATE: Wow it was the MAF. I put my buddies in and the car feels like it only has 10,000 miles on it. Not only did it eat the wrapper also, but whatever was in it didn't agree with the hot wire sensor after about 130,000 miles on it

 

Andy, I am glad your fixed without spending almost two grand like I did. And that was parts alone! I replaced with new everything you can except the lh brain and I am getting about 8 miles to the gal. and blowing rich exhaust still. Other than that the car idles fine and still runs strong . I wonder if those autothority chips screwed something up? anybody with an idea? thanks , Kevin
Replaced , wires , plugs, coils, temp2, MAF , all filters, vac lines, too much to list.

 

Kevin........was your car that rich with poor mpg before the chip swap? If so swap them back with the OEM's.............I have GT mapped eproms in my car and idle and gas consumption was altered to the bad. If your Authority chips are similarly mapped they're expecting the cams and manual transmission GT gearing which dumps fuel to the system at the wrong time.

If you don't have the OEM chips talk to John Speake in England.............I'm swapping my LH eprom back to stock.

 

Kevin:
I had a similar problem with one of my Volvos... bad mileage fouled plugs ran ok at full throttle. It turned out to be the fuel pressure regulator. The pressure was too high, causing too much fuel. Wish I had gone back to basics and checked the fuel pressure early in the game. I now have a fuel pressure gage setup for next time.
--Roy--